Heinzkopf,
That's perfectly normal, those components are mosfets that convert vGPU and vMEM voltages so it's normal they get hot especially when voltmodded and overclocked. All you can do is sink 'n' fan 'em.

The buzzing sound gets the stronger the higher your card OCs. Most likely it's caused by the encased vGPU inductors (big block-like components) on the frontside of the card. It's not dangerous at all.